Covalent bonding occurs between atoms when 1. The potential energy of the shared elec- trons is lower in the bond than it would be if the electrons were not shared between two nuclei 2. The potential energy of the shared elec- trons is independent of the covalent bond, but the potential energy of the newly formed molecule is greater than the individual atoms 3. Covalent bonding occurs when the octet rule is satisfied regardless of the potential en- ergy of the shared electrons 4. The potential energy of the shared elec- trons is higher in the bond than it would be if the electrons were not shared between two nuclei

Answer:

False

Explanation:

Answer:

Explanation:

i hope it helps :)

Answer:

Fractional distillation is a method for separating liquids with different boiling points. For example, liquid ethanol can be separated from a mixture of ethanol and water by fractional distillation. ... The boiling point of ethanol is 78°C and the boiling point of water is 100°C.

Answer:

D.organism

Explanation:

A fungus from the kingdom fungi is an organism

Answer:

D. organism

......................

The question is incomplete, here is the complete question:

A chemist must prepare 550.0 mL of hydrochloric acid solution with a pH of 1.60 at [tex]25^oC[/tex]. He will do this in three steps: Fill a 550.0 mL volumetric flask about halfway with distilled water. Measure out a small volume of concentrated (8.0M) stock hydrochloric acid solution and add it to the flask. Fill the flask to the mark with distilled water. Calculate the volume of concentrated hydrochloric acid that the chemist must measure out in the second step. Round your answer to 2 significant digits.

Answer: The volume of concentrated hydrochloric acid solution is 1.7 mL.

Explanation:

To calculate the hydrogen ion concentration, we use the formula:

[tex]pH=-\log [H^+][/tex]

We are given:

pH = 1.60

Putting values in above equation, we get:

[tex]1.60=-\log [H^+][/tex]

[tex][H^+]=antilog (-1.60)[/tex]

[tex][H^+]=0.0251M[/tex]

To calculate the volume of concentrated solution, we use the equation:

[tex]M_1V_1=M_2V_2[/tex]

where,

[tex]M_1\text{ and }V_1[/tex] = molarity and volume of concentrated acid solution

[tex]M_2\text{ and }V_2[/tex] = molarity and volume of diluted acid solution

We are given:

[tex]M_1=8.0M\\V_1=?mL\\M_2=0.0251M\\V_2=550mL[/tex]

Putting values in above equation, we get:

[tex]8.0\times V_1=0.0251\times 550\\\\V_1=\frac{0.0251\times 550}{8.0}=1.7mL[/tex]

Hence, the volume of concentrated hydrochloric acid solution is 1.7 mL.

Answer:

23 atoms. I hope this helped u

Explanation:

Answer:

protons 19

nuetorns 20

electrons 19

metling point 63.65 C

Explanation:

Answer:

Gallium

Explanation:

Answer:

Gallium

Explanation:

2Ag⁺(aq) + Mg(s)→ 2Ag(s) + Mg²⁺ (aq)

Given

Standard cell notation:

Mg(s) | Mg2+ (aq) || Ag+(aq)| Ag(s)

Required

a balanced redox reaction

Solution

At the cathode the reduction reaction occurs, the anode oxidation reaction occurs

In reaction:  

Ag⁺ + Mg → Ag + Mg²⁺  

half-reactions

Ag⁺ (aq) + e⁻ ---> Ag (s)  x2

2Ag⁺ (aq) + 2e⁻ ---> 2Ag (s)

Mg (s) → Mg²⁺ (aq) + 2e−

a balanced cell reaction

2Ag⁺(aq) + Mg(s)→ 2Ag(s) + Mg²⁺ (aq)

Answer:2Ag⁺(aq) + Mg(s)→ 2Ag(s) + Mg²⁺ (aq)

Explanation:

just took test

Answer:

[tex]C_3H_6[/tex]

Explanation:

Hello!

In this case, since the empirical formula is the smallest representation of the molecular formula, it is known that the times in which the empirical formula is into the molecular formula is a whole number and is computed by dividing the molar mass of the molecular formula by that of the empirical formula as shown below:

[tex]\frac{42.08g/mol}{12.01+1.01x2}= \frac{42.08g/mol}{14.03g/mol}=3[/tex]

Thus, the molecular formula times the empirical formula by 3 to obtain:

[tex]C_3H_6[/tex]

Regards!

Answer:

6.022 x 10²³ electrons

Explanation:

Answer:

They are all mixture

Explanation:

last option

The answer is A. The vibration caused by the waves through the air eventually weaken, which is why sound diminishes easily over distance.

Answer:

. A(n) _______________________________ is matter that is composed of 2 or more different kinds of atoms.

2. A chemical reaction in which energy is released/given off is _____________________________________.

3. A(n) _________________________________ is a process in which substances are changed into other

substances.

4. Matter that is composed of only 1 kind of atom is a(n) ______________________________.

5. ___________________ is the ability to do work and/or transfer heat.

6. A chemical reaction in which energy is absorbed/taken in is _______________________________.

Knew/New

Write down 3 things you already knew about chemical reactions that were confirmed through watching the

video:

1.

2.

3.

Write down 3 new things that you learned from watching the video:

1.

2.

3.

Episode Guide

1. Chemicals can react to form new _________________________________.

2. Chemical reactions happen when ____________________ hook together.

3. Energy is given off during a chemical reaction because ____________________ are combining with other

__________________________.

4. During the "Try this" experiment, we see the students using vinegar and salt to clean old copper pennies.

The copper gets stripped away and the pennies look new again. Explain why you think this happens.

__________________________________________________________________________________________

Answer Key

compound

exothermic

chemical reaction

element

Energy

endothermic

Answers will vary.

Answers will vary.

chemicals

electrons

electrons

electrons

Copper atoms in the penny react with oxygen atoms from the air & together they form copper oxide which

makes the pennies look dull and dirty. The copper oxide dissolves in a weak acid (the vinegar & salt).

5. When vinegar and baking soda react together, the new substance that is produced is ___________________.

6. _______________ & ______________ are both dangerous by themselves, but when they react together they

form table salt.

7. Pyrotechnician is a name given to people who work to create _________________________.

8. In another experiment, we see kids blow up a balloon by mixing together vinegar and baking soda. When

the kids touch the blown up balloon, it is ____________ to the touch. This means that the reaction is

endothermic or exothermic

9. When someone gets hurt playing sports, often times a cold pack is used for the injury. The cold pack takes

up more energy than it gives off and it gets very ___________ to the touch. This means that the reaction taking

place is endothermic or exothermic

10. How do you know baking a cake is a chemical reaction? ________________________________________

11. There are ___________ naturally occurring elements.

12. If elements are in the same group on the periodic table, what does that tell you? ______________________

__________________________________________________________________________________________

True or False

1. When something burns, heat & light are given off. T or F

2. Your stomach growling is an example of a chemical reaction. T or F

3. Water is 1 part hydrogen and 2 parts oxygen. T or F

4. When baking a cake, a chemical reaction takes place. T or F

5. Everything is made of chemicals. T or F

6. Alfred Nobel invented dynamite. T or F

7. You should always wear safety goggles when working with chemicals. T or F

8. Sodium chloride is better known as sugar. T or F

9. A substance can feel a little warm if the reaction is endothermic. T or F

10. When developing film, red light doesn't affect the picture. T or F

11. A cold pack gets cold because the reaction takes more energy than it gives off. T or F

12. If chemicals behave similarly, they are grouped together on the periodic table. T or F

13. Chemical reactions happen when protons link atoms together. T or F

14. When vinegar and baking soda react, oxygen is produced. T or F

15. Fireworks are not an example of chemical reactions. T or F

carbon dioxide

Sodium chlorine

fireworks

warm

cold

The ingredients (flour, milk, eggs, etc.) are changed

Explanation:

Answer:

C₃H₈O₃

Explanation:

Let's assume we have 100 g of said compound. Then we would have:

Now we convert those masses into moles, using their respective atomic weights:

Then we divide those moles by the smallest number among them:

Finally we multiply those numbers by 3, so as to convert the 2.68 of H into an integer:

Thus the empirical formula is C₃H₈O₃

Solution :

lt is given that in 18 mL of water their are [tex]6.022\times 10^{23}[/tex] water molecules.

We know, that 1 molecule of water contains 2 atoms of hydrogen.

Hydrogen atom in 18 mL water is,

[tex]2\times 6.022\times 10^{23} = 12.044 \times 10^{23}[/tex] .

So, number of hydrogen atoms in 1 L = 1000 mL are :

[tex]N = \dfrac{1000}{18}\times 12.044\times 10^{23}\\\\N = 6.69 \times 10^{25}\ atoms[/tex]

Hence, this is the required solution.

Answer:

Slide a magnet through the mixture. When you take the magnet off, the iron filings are going to be attracted to the magnet and the sand will stay in the bowl

Explanation:

Answer:

Density can be used to separate the substances that make up a mixture, because each substance in a mixture has its own density.  For example, if a mixture of sand and oil is placed in water, the sand will sink to the bottom of the container. The sand is more dense than the water.

Explanation:

Please mark me as brainy if this helps

Answer:

0.0344 moles and 1.93g.

Explanation:

Molarity is defined as the ratio between moles of a solute (In this case, KOH), and the volume. With molarity and volume we can solve the moles of solute. With moles of solute we can find mass of the solute as follows:

Moles KOH:

15.2mL = 0.0152L * (2.26mol / L) = 0.0344moles

Mass KOH:

0.0344 moles * (56.11g/mol) = 1.93g of KOH

Answer:

a. 0.528 M .

Explanation:

Hello!

In this case, since the given by-mass percent can be written as:

[tex]\frac{10gCdSO_4}{100g\ sol}[/tex]

By using the density and molar mass of the solute, cadmium sulfate, we can compute the molarity, by also making sure we convert from mL to L of solution:

[tex]M=\frac{10gCdSO_4}{100g\ sol}*\frac{1molCdSO_4}{208.46gCdSO_4} *\frac{1.10g\ sol}{1mL\ sol}*\frac{1000mL}{1L} \\\\ M=0.528M[/tex]

Thereby, the answer is a. 0.528 M .

Best regards.

The molarity of the solution of 10% by mass cadmium sulfate [tex](CdSO_4)[/tex] is approximately 0.479 M. The correct option is C.

To calculate molarity we need to find out how many moles of CdSO4 are present in the solution.

Given:

We need to calculate the mass of [tex]CdSO_4[/tex]:

Mass of [tex]CdSO_4[/tex] = (10% / 100%) * Total mass of the solution

Mass of [tex]CdSO_4[/tex] = (10 / 100) * 1000 g (since the volume is 1 L, and the density is 1.10 g/mL)

Mass of [tex]CdSO_4[/tex] =  100 g

So, the number of moles of CdSO4:

Number of moles of [tex]CdSO_4[/tex] = Mass of CdSO4 / Molar mass of CdSO4

Number of moles of [tex]CdSO_4[/tex] = 100 g / 208.46 g/mol

Number of moles of [tex]CdSO_4[/tex] ≈ 0.479 moles

Then, we calculate the molarity of the solution:

Molarity = Number of moles of CdSO4 / Volume of the solution (in liters)

Molarity = 0.479 moles / 1 L

Molarity ≈ 0.479 M

Hence, the molarity of the solution of 10% by mass cadmium sulfate [tex](CdSO_4)[/tex] is approximately 0.479 M. The correct option is C.

Learn more about Molarity, here:

https://brainly.com/question/31545539

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Answer:

529g/L

Explanation:

The concentration in chemistry is defined as the amount of solute in a determined amount of solution. The concentration in g/L means the amount of grams of solute (In this case, barium acetate), per liter of solution.

To solve this problem we need to find grams of solute (52.9g, already given) and the volume in liters (Converting 100mL to liters):

Volume:

100mL * (1L / 1000mL) = 0.100L

And concentration in g/L is:

52.9g / 0.100L =

Answer:

The volume of the gas increases as the temperature increases.

Explanation:

Gas volume does increase with increasing temperature providing that the pressure remains constant. Temperature and pressure both interact with the gas volume according to the gas Laws and both variables must be accounted for at the same time.

Answer:Comparison of Ionic and Covalent Bonds

In an ionic bond, the atoms are bound together by the electrostatic forces in the attraction between ions of opposite charge. ... For example, sodium (Na), a metal, and chloride (Cl), a nonmetal, form an ionic bond to make NaCl. In a covalent bond, the atoms bond by sharing electrons.

pls   add  Brainliest

Answer:

Explanation:

From the combustion of carbon, the reactions occurring in limited oxygen conditions are:

[tex]C(graphite) + \dfrac{1}{2}O_{2(g)} \to CO_{(g)}[/tex]  

[tex]C(graphite) + O_{2(g)} \to CO_{2(g)}[/tex]  

If it occurs in excess, then any leftover CO changes to CO2. i.e.

[tex]C(graphite) + O_{2(g)} \to CO_{2(g)}[/tex]   ---- (1)

[tex]CO_{(g)} + \dfrac{1}{2}O_{(g)} \to CO_{2(g)}[/tex]          ----- (2)

From (1), the enthalpy change is:

[tex]\Delta H_{rxn1} = \Delta H^0_{fCO_2(g)} - ( \Delta H^0_{f C(graphite)}+ \Delta H^0_{fCO_2(g)}[/tex]

[tex]\Delta H_{rxn1} =-393.5 \ kJ/mol -(0+0)[/tex]

[tex]\Delta H_{rxn1} =-393.5 \ kJ/mol[/tex]

From (2), the enthalpy change is:

[tex]\Delta_{rxn2} = \Delta H^0_{fCO_2(g)} - ( \Delta H^0_{fCO(g)} + \dfrac{1}{2} \Delta H^0_{fO_2(g)})[/tex]

[tex]\Delta_{rxn2} = -393.5 \ kJ/mol -(-110.5 + \dfrac{1}{2}(0))[/tex]

[tex]\Delta_{rxn2} = -283.0 \ kJ/mol[/tex]

Subtracting (2) from (1), we get:

[tex]C(graphite) + O_{2(g)} \to CO_{2(g)} \ \ \ \Delta H_{rxn} = -393.5 \ kJ/mol}[/tex]

[tex]CO_{(g)} + \dfrac{1}{2} O_2(g) \to CO_{2(g)}} \ \ \ \Delta H _{rxn2} = -283.0 \ kJ/mol[/tex]

[tex]C(graphite) + O_{2(g)} \to CO (g) + \dfrac{1}{2}O_{2(g)} \ \ \ \Delta H_{rxn} = -110.5 \ kJ/mol[/tex]

[tex]C(graphite) + \dfrac{1}{2} O_{2(g)} \to CO (g) \ \ \ \Delta H_{rxn} = -110.5 \ kJ/mol[/tex]

The enthalpy change ΔH of the reaction = -110.5 kJ/mol

Answer:

Physical and chemical changes can occur almost everywhere, even in our bodies! Food must be broken down into a form that our cells can use. When we eat, our bodies physically break down food into small pieces. Our bodies also chemically break down those small pieces of food into tiny organic molecules.

Explanation:

Answer:

B. Indicator

Explanation:

An indicator is used to determine whether an acid or alkali has been added to a solution.

An acid or alkali changes the hydrogen ion concentration in solution. This is indicated by the pH of the solution after which the acid or alkali has been added.